package entity;

import java.util.ArrayList;
import java.util.List;

public class CardCollection {
    public final List<CreditCard> cards;
    private static CardCollection instance = null;
    private CardCollection() {
        cards = new ArrayList<>();
    }
    public static CardCollection getInstance() {
        if (instance == null) {
            instance = new CardCollection();
        }
        return instance;
    }
    public void addCard(CreditCard card) {
        cards.add(card);
    }
}
